* {
  margin: 0;
  padding: 0;
}

.flex {
  display: flex;
}

.wrap {
  display: flex;
  flex-wrap: wrap;
}

.align-center {
  display: flex;
  align-items: center;
}

.avatar {
  display: flex;
  justify-content: center;
  align-content: center;

  img {
    width: 100%;
    height: 100%;
    border-radius: 50%;
  }
}

.noselect {
  -moz-user-select: none;
  /* 火狐 */
  -webkit-user-select: none;
  /* 谷歌、Safari */
  -ms-user-select: none;
  /* IE10+ */
  user-select: none;
}

.back{
  background-color: white;
}
html{
  background-color: rgb(245, 245, 245);
}